S13 SR20DET mods....

[SrSLeePeR]

Hell everyone. I'm purchasing a Blacktop S13 SR20DET engine along with a FMIC, GReddy Type-S BOV, LSD, and a 3" DP. All of this will be on the engine when I get it. I'm very excited on driving a turbo engine and this will be my first experience. ( I DO know about turbos though...) Anyways, Ill be missing he exhaust but the person/place I will be getting the motor from says that exhaust shouldt effect anything but high-end power. Will the stock exhaust be okay with the mods that I listed? I kind of dont want exhaust because I want to hear the sound of the engine, but not having an exhaust on a turbo car will certainly keep it quiet and hiding to potential of the car. Will I be safe with an FMIC, BOV, 3"DP going out a stock exhaust? I really dont want to lose lots of power but if its 3-5 hp that I MIGHT lose, its okay..

Also, the BOV will be located in the fenderlining where the OEM stock recirculating BOV goes....Would the aftermarket be louder in the engine bay or will be be louder in the fenderlining? Ill be having a good BOV that functions great, but now that I dont have to worry about functionality, I wanna worry about where it will sound louder, in the wheelwell or in the engine bay?

Thanks for taking the time to read and answer my questions..This site is my new home!-Albert

[SpeedFreak]

One thing your going to run into with having a stock exhaust is that you will have a lot more turbo lag because of it and you will lose hp as well.

[Daunttless]

If you keep the stock exhaust, not only will you loose power, you'll kill your turbo. It will lead a short, very unhappy, very hot life and self destruct. The stock exhaust will not flow enough for a turbo charged application. Stunningly enough theres a reason turbo cars come stock with larger exhausts. : )

If you really don't want a cat back or something, I'd say at least have a muffler shop put in straighter, as mandrel bent as possible exhaust tubing in 2.75 - 3 inches, preferably 3. If you just want to buy yourself some time until you get a catback, do mild steel because it will be really cheap, if you don't plan on going to a catback system for a long, long time, spend the extra cash on stainless steel.

You may wish to get a bigger fuel pump, its just a safe upgrade to have.

Also, I'm not sure if a 3 inch downpipe will even line up with the stock setup...

Unless they are recirculating your BOV, on a stock SR20 setup you're going to stumble and choke everytime you shift on boost, because the SR20 uses a mafs sensor, which will be way upstream of the BOV, so when the BOV releases all that air to prevent compressor surge, the MAFs still thinks its there, the throttle body opens back up to no air, fuel gets poured in and your engines going to stutter, noticably.

It will be louded in the fenderlining because it has a more direct access to the oustide world, under the hood it will be loud, but not as loud.

[Ace]

Two things don't get your lsd until later get an exhaust. 2nd Dauntless are you saying that the bov should be put on right next to the throttle body, because HeavyThrottle the place where im getting my SR setup has a hot pipe that goes from the turbo to the FMIC and they put a bov flange on there. But should I just have pipe there and have a muffler shop weld the bov next to the throttle body.

[Daunttless]

The hotpipe is usable, however the closer to the throttle body the better generally, it provides a mucher quicker response for the BOVs duties. However the hot pipe is another perfectly acceptable place. : )

[hurddawg]

SCC used the 3" Greddy downpipe on the stock exhaust. That was a 89 240.

just info.

[I H8 UR DSM]

The hotpipe is usable, however the closer to the throttle body the better generally, it provides a mucher quicker response for the BOVs duties. However the hot pipe is another perfectly acceptable place. : )

I totally disagree there....You're telling him to put the BOV on the cold air side of the intercooler before the throttle body? Yes it might give a slight slight slight difference in throttle response, but your also blowing off cold air...most of use find it more efficient to have the bov before the intercooler.....AND the fact that putting the BOV closer to the turbo the better....You want to have as little air forced back into the turbo as possible, and placing the bov closer to the turbo allows for that.....Thats pretty much your whole point of having a BOV...I know there are some benefits of what your suggesting, but thats not the most common placement, and definitly not the best for the longevity of the turbo.

am i missing something about your comment Dauntt?

[SrSLeePeR]

Quote »Two things don't get your lsd until later get an exhaust. 2nd Dauntless are you saying that the bov should be put on right next to the throttle body, because HeavyThrottle the place where im getting my SR setup has a hot pipe that goes from the turbo to the FMIC and they put a bov flange on there. But should I just have pipe there and have a muffler shop weld the bov next to the throttle body.[/quote]The thing is everything I listed is already on the motor. I'm just waiting to get a car to drop it in. I'm not too sure about what you guys are saying about the BOV..I'm still a little confused. I'm assuming the BOV was put there because the stock one was in the same location and it had to be there for a reason right? I'm not trying to argue or anything, because I'm not too sure myself. I just want to know where the best place to place it would be. I know for a fact I dont want it right before the TB...I want it after the turbo, before the IC but I dont know if I should leave it in the fenderlining, or have it where everyone else has it which is right after the turbo.

As for the LSD, everything is ready. The only thing is I'm missing the exhaust. now I'm assuming the OEM exhaust is maybe 2-1/4 or so. I'm still going to be boosting stock which is 7psi. What I dont get is for instant...boosted DSM's have stock boost around 7 as well. If its okay for them to run the tiny stock exhaust system, how come its not okay for the SR to run it as well because both are boosting 7psi and wouldnt MY SR20DET be safer since it does have the large FMIC?

Thanks for the replies guys..I'd like to hear more opinions about this topic...

-Albert

[hurddawg]

here's another....88-92 Mazda 626/MX6 GT (turbo, its a 2.2L I4) has a stock 2" exhaust. It runs 7psi-9psi (9psi is midrange only).

The point is that your engine is going to have a rough life. The more backpressure in the exhaust more exhaust gas reversion = more detonation prone, less power because of decreased VE, premature failure of exhaust valves, not to mention the extra heat the cooling system will have to carry.

The extra heat acculimated in the turbo will transmit to higher intake charges as well (however slightly). Even though you do have a FMIC, it will help HP, because it'll be taking out more heat compared to the stock IC, but not to its full potential. But having a large FMIC will do diddly-squat for reduction in exhaust gas reversion. All the FMIC will do is help reduce detonation, but won't help the engine in the other cases I mentioned above.

Its ok to run the stock exhaust, it did come the factory that way. But it doesn't mean it was done right. Remember enthusiats don't make cars, marketers do, they'll cut corners anywhere. I mean temporarily would be perfectly fine.

Taking the MX6 for example, the turbo typically dies around 150K. I think for an import, that's premature given the fact its a watercooled turbo. I think the benefits outweigh the disadvantages (costs) heavily here.

[Daunttless]

Jesse and I had differing viewpoints as to our definition of hotpipe, I had the same problem on the old board with downpipe/midpipe/testpipe/dumppipe, etc. : ) By hotpipe I meant conected directly to the turbo, and Jesse meant the entire pipe between the turbo and intercooler. I would put it in the fenderlining, as its closer to the throttle bottle but farther away from the turbo, better response and less chance of accidental compressor surge. Jesse has his in the fenderlining. : ) Sorry for the confusion, right next to the turbo would work just fine, but I like the fenderlining, and if you are into it, a lot of people think its louder out there.

And, everything that hurddawg said. : )

[SrSLeePeR]

Thanks...This forum keeps getting bigger and bigger, better and better...! :ylsuper

[ST240]

Umm call me an idiot if you want.

But arent most if not ALL BOVs located after the intercooler!?

-Andre

[SrSLeePeR]

no...

[Ace]

ST240 you've been looking at some turbo Hondas huh. Admit it. Just joking, but I have to agree that there are some cars that have them after the intercooler right before the throttle body. But from what I've heard from this post, I can't really figure why they do that?

[I H8 UR DSM]

Jesse and I had differing viewpoints as to our definition of hotpipe, I had the same problem on the old board with downpipe/midpipe/testpipe/dumppipe, etc. : ) By hotpipe I meant conected directly to the turbo, and Jesse meant the entire pipe between the turbo and intercooler. I would put it in the fenderlining, as its closer to the throttle bottle but farther away from the turbo, better response and less chance of accidental compressor surge. Jesse has his in the fenderlining. : ) Sorry for the confusion, right next to the turbo would work just fine, but I like the fenderlining, and if you are into it, a lot of people think its louder out there.

And, everything that hurddawg said. : )

Yes, but i still can't understand you at all...Yes, mine is in the fenderlining, on the side of the turbo....you keep mentioning Throttle Body, and Fenderlining, which would refer to the other side of the car. My BOV is not on the side of the TB, but on the side of the turbo....conprende'? Hotpipe, drivers side...Throttle body, passenger side. I have by BOV located on the drivers side..(IN AMERICAN 240>....LHD)....so its closer to the Turbo than it is to the throttle body, and its on the inlet side of the intercooler....daunttless is confusing.

[Daunttless]

Thank you Jesse, I realize the difference. =P I realize the throttle body is on the passenger, and the turbo is on the driver, and I was also talking about the drivers side fenderlining, you just can't comprehend with your substandard education. Sheesh, with a response like that I almost thought you were one of the Canadians who's been givin us trouble. : )

:icesangel

[I H8 UR DSM]

I would put it in the fenderlining, as its closer to the throttle bottle but farther away from the turbo,

well, my intelligence leads me to believe by that post, that you are refering to the fenderlining in the passenger side of a US 240...correct?

If its in the driver side fenderlining, it would be closer to the turbo than the TB right?....

where did you get your education? IowA? figures....:thinker :thinker :thinker

[killjoy]

Why is the bov on an s13 on the hot side and the bov on an s14 on the cold side?

[Nils]

Get an exhaust and have it over with..... you need a bigger exhaust since the turbo is going to try to shoot out as much exhaust gas as possible.

Eventhough I know it is not Jessies favorite spot I have to agree with Daunt on the location of the BoV, I too would put mine as close to the TB as possible, I know that will result in a loss of cold air but I'd rather loose cold air than to snapping a shaft or something in the turbo. Putting the BoV by the TB ensures that the BoV releases as soon as the TB closes. This is what I did on my Supra and it works fine.

When it really comes down to it I dont think it makes that much of a difference where the BoV goes aslong as you have one, comes down to preference. Another example of different preferences is where to put the EGT probe, some prefer to put it in the DP after the turbo and some prefer to put them in a runner on the exhaust manifold before the turbo.... what to do.. what to do =)

take care,nils

[Chris69427]

I gotta side with Nils on the BOV issue. Think about it, guys, when the throttle body is open, all this air is just going into the engine, right? So what difference is it to the turbo, if instead of going into the engine, the air is vented out through the BOV right by the TB? None! So why confuse your MAF sensor by locating the BOV close to the turbo shaft? It only feels like it's releaving the pressure closer to the source, but the turbo doesn't know the where the BOV is; it's just pumping air and if that air goes somewhere even if into the atmosphere after the intercooler, it's not hurting the turbo any more than when the throttle blades are open at full boost under normal operation. Long winded, I am, yes, but doesn't that make sense (if you can decipher what I'm trying to say)?Later, Chris

[SRdS14]

srSLEEPER...now that's some dedication. my man has a damn motor...and NO CAR. hell ya bro... :ylsuper

[SrSLeePeR]

haha..yeah...I got the car about a week after and the first thing I did was take it to get it swapped..I dont know how it feels like to drive a KA...I started off with an SR20DETwhen I first drove it...and I'm in love....

[I H8 UR DSM]

I gotta side with Nils on the BOV issue. Think about it, guys, when the throttle body is open, all this air is just going into the engine, right? So what difference is it to the turbo, if instead of going into the engine, the air is vented out through the BOV right by the TB? None! So why confuse your MAF sensor by locating the BOV close to the turbo shaft? It only feels like it's releaving the pressure closer to the source, but the turbo doesn't know the where the BOV is; it's just pumping air and if that air goes somewhere even if into the atmosphere after the intercooler, it's not hurting the turbo any more than when the throttle blades are open at full boost under normal operation. Long winded, I am, yes, but doesn't that make sense (if you can decipher what I'm trying to say)?Later, Chris

id consider the fact that the most important reason for having a bov, is to release pressure from going back into the turbo in the wrong direction....putting as close to the turbo as possible would extend the life of your turbo the most...

[SrSLeePeR]

I've had mines in the drivers side fender ever since I got the swap....its the best location in my opinion....plus its louder....What more can you ask for...GReddy Type-S....

[Nils]

id consider the fact that the most important reason for having a bov, is to release pressure from going back into the turbo in the wrong direction....putting as close to the turbo as possible would extend the life of your turbo the most...

Well, I dont know if that is necessarily true. To my knowledge it would be "ideally" better to protect the turbo from "back wash" by putting the BoV closer to the TB where the air is stopped and returned back towards the turbo. If the BoV is located at the point of return the air pressure going back to the turbo has to be less. I regularly boost well over 1.6bar, I have my BoV very close to the TB and have not had *any* turbo problems for 2 years. I am not saying that putting the BoV by the turbo is bad or that it wont work.

Again, I really dont think it matters that much where the BoV is located.. it works either way.

take care,nils

[BinaryVertigo]

Nils: "When it really comes down to it I dont think it makes that much of a difference where the BoV goes aslong as you have one, comes down to preference."

IMO the BOV should be as close to the turbine as possible to allieviate the amount of work the turbine has to do. Take into consideration that if the BOV is place after the IC and nearer to the TB, the turbine still has to push ambient air through the IC, and what's worst is that mass of air exits right after. Now if the BOV is put nearer to the turbine, when the TB closes, compression surge runs from the TB back through the IC and hits the BOV, while MAINTAINING BOOST and lettin all the HOT AIR that's comming from the turbine out (hence it's more effective for the BOV to be in the fenderliner so it doesnt contribute to engine temperature, not just because it's "louder"). This also lets the air that's ALREADY in the IC to stay in there a bit more. More cooling equals denser air ( MASS remains the same) which ultimately reduce chances of detonation. ALSO, with the BOV nearer to the TB, you are releasing perfectly condensed air comming from the IC. Why do that when you can release the hot air that's comming from the turbine, before making it do extra work by pushing the air through the IC to be wasted.

If you like your BOV near your throttle body and not in the fenderliner so that every1 can marvel at it, then by all means, pursuit your happiness. However, you should get a Honda and turbocharge it instead of doing something like that to a Nissan

IMHO-Demitri

BTW Nils- This is in no way to attack your comment...i just felt i had something to say..."you" refers to the universal "you" and not "you" Nils...thanks

[tomS14]

I got a front clip S14 and it had the Biltz BOV after the intercooler before the plastic pipe that run over the fan shoud to the intake intake m. , next to the crank sensor not attach to notting but the Aluminum pipe.

[Nils]

-Demitri,No offense taken and I understand what you are saying =)

Lets not forget that a BoV is a turbo safety device, nothing more. To expect performance gains from BoV placement is a little dreamy, maybe a little hopeful. Aslong as the BoV is placed inbetween the turbine and the TB it will do its job. However, compressor surge starts at the TB, therefore in the best interest of the turbo, placing the BoV closer to the TB will end the surge sooner and protect the turbo from any radical backspin. To keep one fluid air motion is easier on the turbo and all the hose couplings, if air keeps on rushing back and forward through the IC and all the couplings you are radically upsetting the flow back and forward, I just dont see the logic in that. I know alot of guys that push big boost with their BoV placed close to the turbine and they pop hoses all the time. The *only* reason I have a boV is to prevent the turbine shaft from snapping in two, not to make the turbo work less. I have never heard of anyone detonating after shifting, due to a BoV realease.

Now, I will admit that I know very little about 240's in general and my Supra does not even use the MAF, the VPC replaced the MAF with speed density measurment. What we are discussing is a more generalized topic though and could be applied to all kinds of turbo charged vehicles.

I dont think any of us have definite proof for any of our theories, I dont think anyone here has done the research to prove anyone else wrong, so lets leave it at that. I have my beliefs and you have yours =)

take care,nils

btw - Demitri, No need to knock on the Honda guys out there, I know alot of very serious "honda" road racers that are *very* fast on the track. I also see many riced out 240's (along with 20 other car makes) on the streets , so to make a comment like you did at the end of your post could apply to any car make and model.... more of an owner thing than a car model thing....

[Movingviolation240]

The whole point of a BOV is to stop the air from bouncing back into the turbo, so why not eleminate the problem where it will start the bounce, not at the end of the system where it has already gained great momentum. Also if you have the BOV right next to your turbo, you just let all the pressure out of your 2.5in pipes, and the massive FMIC, that's a lot of air to replace, which leads to more turbo lag as it has to pump that area back up to 20psi of line pressure. If it's at the end of the system it only lets off what needs to be let off, and therefore leaves more pressure in the pipes so it takes less time for them to pump back up later. The turbo is just sending air down the line throught the system, it dosn't know or care if it goes out the other end through a throttlebody or through an open blow off that's 6in further back.

The ONLY advantage to putting it on the hot side is that it's a shorter track to re-route it back into the intake infront of the turbo if you want to recirculate it.

Also if you look, Supra's, WRX's, and Saab's all put the blow off closer to the TB than the turbo.

that's my theory,

Paul

[ChickenBoo]

where did you get your education? IowA? figures....:thinker :thinker :thinker

You got a problem with Iowa? Why don't you come down here and we'll throw a cow at you or something... ; )